A
I think that Russia would have won the war eventually, but I think that it would have been so exhausted that the Cold War might not have happened. Germany would probably have reached Moscow, but it is doubtful that it would have held on the end.Russia was simply too huge for anyone except the Russians to rule.
B
Being half German and having several relatives who had served on the Easter Front, I am biased towards Germany. I do regard both regimes to be as horrendous as the other. With the Communists anybody could be targeted, but no specific ethnic group. With the Nazi regime, if one wasn't belonging to any of the targeted groups one was relatively safe.